#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef double db;
typedef string str;
typedef pair<int,int> pi;
typedef pair<ll,ll> pl;
typedef pair<db,db> pd;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<db> vd;
typedef vector<str> vs;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<pd> vpd;
#define mp make_pair
#define f first
#define s second
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend()
#define rsz resize
#define ins insert
#define ft front()
#define bk back()
#define pf push_front
#define pb push_back
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)
const int MOD = 1e9+7; // 998244353;
const int MX = 2e5+5;
const ll INF = 1e18;
const ld PI = acos((ld)-1);
const int xd[4] = {1,0,-1,0}, yd[4] = {0,1,0,-1};
template<class T> bool ckmin(T& a, const T& b) {
return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) {
return a < b ? a = b, 1 : 0; }
int pct(int x) { return __builtin_popcount(x); }
int bit(int x) { return 31-__builtin_clz(x); } // floor(log2(x))
int cdiv(int a, int b) { return a/b+!(a<0||a%b == 0); } // division of a by b rounded up, assumes b > 0
// INPUT
template<class A> void re(complex<A>& c);
template<class A, class B> void re(pair<A,B>& p);
template<class A> void re(vector<A>& v);
template<class A, size_t SZ> void re(array<A,SZ>& a);
template<class T> void re(T& x) { cin >> x; }
void re(db& d) { str t; re(t); d = stod(t); }
void re(ld& d) { str t; re(t); d = stold(t); }
template<class H, class... T> void re(H& h, T&... t) { re(h); re(t...); }
template<class A> void re(complex<A>& c) { A a,b; re(a,b); c = {a,b}; }
template<class A, class B> void re(pair<A,B>& p) { re(p.f,p.s); }
template<class A> void re(vector<A>& x) { trav(a,x) re(a); }
template<class A, size_t SZ> void re(array<A,SZ>& x) { trav(a,x) re(a); }
// TO_STRING
#define ts to_string
template<class A, class B> str ts(pair<A,B> p);
template<class A> str ts(complex<A> c) { return ts(mp(c.real(),c.imag())); }
str ts(bool b) { return b ? "true" : "false"; }
str ts(char c) { str s = ""; s += c; return s; }
str ts(str s) { return s; }
str ts(const char* s) { return (str)s; }
str ts(vector<bool> v) {
bool fst = 1; str res = "{";
F0R(i,sz(v)) {
if (!fst) res += ", ";
fst = 0; res += ts(v[i]);
}
res += "}"; return res;
}
template<size_t SZ> str ts(bitset<SZ> b) {
str res = ""; F0R(i,SZ) res += char('0'+b[i]);
return res; }
template<class T> str ts(T v) {
bool fst = 1; str res = "{";
for (const auto& x: v) {
if (!fst) res += ", ";
fst = 0; res += ts(x);
}
res += "}"; return res;
}
template<class A, class B> str ts(pair<A,B> p) {
return "("+ts(p.f)+", "+ts(p.s)+")"; }
// OUTPUT
template<class A> void pr(A x) { cout << ts(x); }
template<class H, class... T> void pr(const H& h, const T&... t) {
pr(h); pr(t...); }
void ps() { pr("\n"); } // print w/ spaces
template<class H, class... T> void ps(const H& h, const T&... t) {
pr(h); if (sizeof...(t)) pr(" "); ps(t...); }
// DEBUG
void DBG() { cerr << "]" << endl; }
template<class H, class... T> void DBG(H h, T... t) {
cerr << to_string(h); if (sizeof...(t)) cerr << ", ";
DBG(t...); }
#ifdef LOCAL // compile with -DLOCAL
#define dbg(...) cerr << "[" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 42
#endif
// FILE I/O
void setIn(string s) { freopen(s.c_str(),"r",stdin); }
void setOut(string s) { freopen(s.c_str(),"w",stdout); }
void unsyncIO() { ios_base::sync_with_stdio(0); cin.tie(0); }
void setIO(string s = "") {
unsyncIO();
// cin.exceptions(cin.failbit);
// throws exception when do smth illegal
// ex. try to read letter into int
if (sz(s)) { setIn(s+".in"), setOut(s+".out"); } // for USACO
}
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count());
int B[30005];
int P[30005];
set<int> doges[30005];
//bool hasdoge[30005];
set<pi> m;
bool visited[30005];
int main() {
setIO();
int N, M;
cin >> N >> M;
for(int i = 0; i < M; i++){
cin >> B[i] >> P[i];
doges[B[i]].insert(P[i]);
//hasdoge[B[i]] = 1;
}
int EN = B[1];
queue<array<int, 3>> q;
array<int, 3> beg = {B[0], P[0], 0};
q.push(beg);
while(sz(q)){
array<int, 3> dat = q.front();
q.pop();
if(dat[0] < 0 || dat[0] >= N) continue;
//if(m.count(mp(dat[0], dat[1]))) continue;
//m.insert(mp(dat[0], dat[1]));
if(dat[0] == EN){
ps(dat[2]);
return 0;
}
if(visited[dat[0]] == 0){
for(auto u: doges[dat[0]]){
array<int, 3> nm1 = {dat[0]-u, u, dat[2]+1};
if(!m.count(mp(dat[0]-u, u))){
m.insert(mp(dat[0]-u, u));
q.push(nm1);
}
array<int, 3> nm2 = {dat[0]+u, u, dat[2]+1};
if(!m.count(mp(dat[0]+u, u))){
m.insert(mp(dat[0]+u, u));
q.push(nm2);
}
}
visited[dat[0]] = 1;
}
array<int, 3> nl = {dat[0]-dat[1], dat[1], dat[2]+1};
if(!m.count(mp(dat[0]-dat[1], dat[1]))){
m.insert(mp(dat[0]-dat[1], dat[1]));
q.push(nl);
}
array<int, 3> nr = {dat[0]+dat[1], dat[1], dat[2]+1};
if(!m.count(mp(dat[0]+dat[1], dat[1]))){
m.insert(mp(dat[0]+dat[1], dat[1]));
q.push(nr);
}
}
ps(-1);
// you should actually read the stuff at the bottom
}
/* stuff you should look for
* int overflow, array bounds
* special cases (n=1?)
* do smth instead of nothing and stay organized
* WRITE STUFF DOWN
*/
Compilation message
skyscraper.cpp: In function 'void setIn(std::__cxx11::string)':
skyscraper.cpp:123:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
void setIn(string s) { freopen(s.c_str(),"r",stdin); }
~~~~~~~^~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp: In function 'void setOut(std::__cxx11::string)':
skyscraper.cpp:124:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
void setOut(string s) { freopen(s.c_str(),"w",stdout); }
~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
1792 KB |
Output is correct |
2 |
Correct |
5 ms |
1792 KB |
Output is correct |
3 |
Correct |
5 ms |
1792 KB |
Output is correct |
4 |
Correct |
5 ms |
1792 KB |
Output is correct |
5 |
Correct |
5 ms |
1792 KB |
Output is correct |
6 |
Correct |
5 ms |
1792 KB |
Output is correct |
7 |
Correct |
5 ms |
1792 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
1792 KB |
Output is correct |
2 |
Correct |
5 ms |
1792 KB |
Output is correct |
3 |
Correct |
5 ms |
1792 KB |
Output is correct |
4 |
Correct |
5 ms |
1792 KB |
Output is correct |
5 |
Correct |
5 ms |
1792 KB |
Output is correct |
6 |
Correct |
5 ms |
1792 KB |
Output is correct |
7 |
Correct |
5 ms |
1792 KB |
Output is correct |
8 |
Correct |
5 ms |
1792 KB |
Output is correct |
9 |
Correct |
5 ms |
1792 KB |
Output is correct |
10 |
Correct |
5 ms |
1792 KB |
Output is correct |
11 |
Correct |
6 ms |
1792 KB |
Output is correct |
12 |
Correct |
5 ms |
1792 KB |
Output is correct |
13 |
Correct |
5 ms |
1792 KB |
Output is correct |
14 |
Correct |
9 ms |
2304 KB |
Output is correct |
15 |
Correct |
8 ms |
2304 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
1792 KB |
Output is correct |
2 |
Correct |
5 ms |
1792 KB |
Output is correct |
3 |
Correct |
5 ms |
1792 KB |
Output is correct |
4 |
Correct |
5 ms |
1792 KB |
Output is correct |
5 |
Correct |
5 ms |
1792 KB |
Output is correct |
6 |
Correct |
5 ms |
1792 KB |
Output is correct |
7 |
Correct |
5 ms |
1792 KB |
Output is correct |
8 |
Correct |
5 ms |
1792 KB |
Output is correct |
9 |
Correct |
5 ms |
1792 KB |
Output is correct |
10 |
Correct |
5 ms |
1792 KB |
Output is correct |
11 |
Correct |
6 ms |
1792 KB |
Output is correct |
12 |
Correct |
6 ms |
1792 KB |
Output is correct |
13 |
Correct |
6 ms |
1792 KB |
Output is correct |
14 |
Correct |
9 ms |
2304 KB |
Output is correct |
15 |
Correct |
8 ms |
2304 KB |
Output is correct |
16 |
Correct |
5 ms |
1792 KB |
Output is correct |
17 |
Correct |
7 ms |
2048 KB |
Output is correct |
18 |
Correct |
5 ms |
1792 KB |
Output is correct |
19 |
Correct |
5 ms |
1792 KB |
Output is correct |
20 |
Correct |
6 ms |
1920 KB |
Output is correct |
21 |
Correct |
6 ms |
1792 KB |
Output is correct |
22 |
Correct |
6 ms |
1792 KB |
Output is correct |
23 |
Correct |
8 ms |
2176 KB |
Output is correct |
24 |
Correct |
10 ms |
2304 KB |
Output is correct |
25 |
Correct |
6 ms |
1920 KB |
Output is correct |
26 |
Correct |
6 ms |
1920 KB |
Output is correct |
27 |
Correct |
7 ms |
2048 KB |
Output is correct |
28 |
Correct |
18 ms |
2944 KB |
Output is correct |
29 |
Correct |
38 ms |
4728 KB |
Output is correct |
30 |
Correct |
12 ms |
2560 KB |
Output is correct |
31 |
Correct |
21 ms |
3456 KB |
Output is correct |
32 |
Correct |
16 ms |
2944 KB |
Output is correct |
33 |
Correct |
82 ms |
7800 KB |
Output is correct |
34 |
Correct |
41 ms |
5112 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
1792 KB |
Output is correct |
2 |
Correct |
5 ms |
1792 KB |
Output is correct |
3 |
Correct |
5 ms |
1792 KB |
Output is correct |
4 |
Correct |
5 ms |
1792 KB |
Output is correct |
5 |
Correct |
5 ms |
1792 KB |
Output is correct |
6 |
Correct |
6 ms |
1792 KB |
Output is correct |
7 |
Correct |
5 ms |
1792 KB |
Output is correct |
8 |
Correct |
5 ms |
1792 KB |
Output is correct |
9 |
Correct |
5 ms |
1792 KB |
Output is correct |
10 |
Correct |
5 ms |
1792 KB |
Output is correct |
11 |
Correct |
6 ms |
1792 KB |
Output is correct |
12 |
Correct |
5 ms |
1792 KB |
Output is correct |
13 |
Correct |
5 ms |
1792 KB |
Output is correct |
14 |
Correct |
10 ms |
2304 KB |
Output is correct |
15 |
Correct |
8 ms |
2304 KB |
Output is correct |
16 |
Correct |
5 ms |
1792 KB |
Output is correct |
17 |
Correct |
7 ms |
2048 KB |
Output is correct |
18 |
Correct |
6 ms |
1792 KB |
Output is correct |
19 |
Correct |
5 ms |
1792 KB |
Output is correct |
20 |
Correct |
6 ms |
2048 KB |
Output is correct |
21 |
Correct |
6 ms |
1792 KB |
Output is correct |
22 |
Correct |
6 ms |
1792 KB |
Output is correct |
23 |
Correct |
8 ms |
2048 KB |
Output is correct |
24 |
Correct |
12 ms |
2304 KB |
Output is correct |
25 |
Correct |
6 ms |
1920 KB |
Output is correct |
26 |
Correct |
6 ms |
1920 KB |
Output is correct |
27 |
Correct |
8 ms |
2048 KB |
Output is correct |
28 |
Correct |
16 ms |
2944 KB |
Output is correct |
29 |
Correct |
38 ms |
4796 KB |
Output is correct |
30 |
Correct |
13 ms |
2560 KB |
Output is correct |
31 |
Correct |
21 ms |
3456 KB |
Output is correct |
32 |
Correct |
16 ms |
2944 KB |
Output is correct |
33 |
Correct |
82 ms |
7800 KB |
Output is correct |
34 |
Correct |
41 ms |
5116 KB |
Output is correct |
35 |
Correct |
41 ms |
6400 KB |
Output is correct |
36 |
Correct |
7 ms |
2176 KB |
Output is correct |
37 |
Correct |
23 ms |
4352 KB |
Output is correct |
38 |
Correct |
25 ms |
4856 KB |
Output is correct |
39 |
Correct |
15 ms |
3456 KB |
Output is correct |
40 |
Correct |
17 ms |
3712 KB |
Output is correct |
41 |
Correct |
20 ms |
4096 KB |
Output is correct |
42 |
Correct |
11 ms |
2176 KB |
Output is correct |
43 |
Correct |
11 ms |
2176 KB |
Output is correct |
44 |
Correct |
10 ms |
2176 KB |
Output is correct |
45 |
Correct |
590 ms |
29352 KB |
Output is correct |
46 |
Correct |
239 ms |
18428 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
1792 KB |
Output is correct |
2 |
Correct |
5 ms |
1792 KB |
Output is correct |
3 |
Correct |
5 ms |
1792 KB |
Output is correct |
4 |
Correct |
5 ms |
1792 KB |
Output is correct |
5 |
Correct |
5 ms |
1792 KB |
Output is correct |
6 |
Correct |
6 ms |
1792 KB |
Output is correct |
7 |
Correct |
5 ms |
1792 KB |
Output is correct |
8 |
Correct |
5 ms |
1792 KB |
Output is correct |
9 |
Correct |
5 ms |
1792 KB |
Output is correct |
10 |
Correct |
6 ms |
1792 KB |
Output is correct |
11 |
Correct |
6 ms |
1792 KB |
Output is correct |
12 |
Correct |
6 ms |
1792 KB |
Output is correct |
13 |
Correct |
6 ms |
1792 KB |
Output is correct |
14 |
Correct |
9 ms |
2304 KB |
Output is correct |
15 |
Correct |
8 ms |
2304 KB |
Output is correct |
16 |
Correct |
6 ms |
1792 KB |
Output is correct |
17 |
Correct |
7 ms |
2048 KB |
Output is correct |
18 |
Correct |
7 ms |
1792 KB |
Output is correct |
19 |
Correct |
5 ms |
1792 KB |
Output is correct |
20 |
Correct |
6 ms |
1920 KB |
Output is correct |
21 |
Correct |
6 ms |
1792 KB |
Output is correct |
22 |
Correct |
6 ms |
1792 KB |
Output is correct |
23 |
Correct |
8 ms |
2176 KB |
Output is correct |
24 |
Correct |
10 ms |
2304 KB |
Output is correct |
25 |
Correct |
6 ms |
1920 KB |
Output is correct |
26 |
Correct |
6 ms |
1920 KB |
Output is correct |
27 |
Correct |
7 ms |
2048 KB |
Output is correct |
28 |
Correct |
16 ms |
2944 KB |
Output is correct |
29 |
Correct |
39 ms |
4728 KB |
Output is correct |
30 |
Correct |
12 ms |
2560 KB |
Output is correct |
31 |
Correct |
23 ms |
3456 KB |
Output is correct |
32 |
Correct |
16 ms |
2944 KB |
Output is correct |
33 |
Correct |
83 ms |
7800 KB |
Output is correct |
34 |
Correct |
42 ms |
5112 KB |
Output is correct |
35 |
Correct |
42 ms |
6392 KB |
Output is correct |
36 |
Correct |
7 ms |
2048 KB |
Output is correct |
37 |
Correct |
23 ms |
4352 KB |
Output is correct |
38 |
Correct |
25 ms |
4736 KB |
Output is correct |
39 |
Correct |
16 ms |
3456 KB |
Output is correct |
40 |
Correct |
17 ms |
3712 KB |
Output is correct |
41 |
Correct |
21 ms |
4096 KB |
Output is correct |
42 |
Correct |
10 ms |
2176 KB |
Output is correct |
43 |
Correct |
11 ms |
2176 KB |
Output is correct |
44 |
Correct |
11 ms |
2176 KB |
Output is correct |
45 |
Correct |
644 ms |
29212 KB |
Output is correct |
46 |
Correct |
258 ms |
18424 KB |
Output is correct |
47 |
Correct |
19 ms |
3968 KB |
Output is correct |
48 |
Correct |
17 ms |
2944 KB |
Output is correct |
49 |
Correct |
14 ms |
2992 KB |
Output is correct |
50 |
Correct |
10 ms |
2560 KB |
Output is correct |
51 |
Correct |
57 ms |
6776 KB |
Output is correct |
52 |
Correct |
79 ms |
8060 KB |
Output is correct |
53 |
Correct |
27 ms |
3968 KB |
Output is correct |
54 |
Correct |
10 ms |
2560 KB |
Output is correct |
55 |
Correct |
12 ms |
2944 KB |
Output is correct |
56 |
Correct |
25 ms |
4864 KB |
Output is correct |
57 |
Correct |
7 ms |
1920 KB |
Output is correct |
58 |
Correct |
33 ms |
5240 KB |
Output is correct |
59 |
Correct |
32 ms |
4728 KB |
Output is correct |
60 |
Correct |
32 ms |
4728 KB |
Output is correct |
61 |
Correct |
38 ms |
4728 KB |
Output is correct |
62 |
Correct |
538 ms |
26976 KB |
Output is correct |
63 |
Execution timed out |
1097 ms |
47276 KB |
Time limit exceeded |
64 |
Halted |
0 ms |
0 KB |
- |